Thread: GetStdHandle() returns INVALID_HANDLE_VALUE

I am really wigging out bro. I have been having weird problem after odd problem with this app I'm working on.
Okay, I was working on this code on my pc at home (running xp pro) with no worries. Now here at work (running 98se), I run it and am having my mind boggled. Check it:

Code:

hSaveStdin = GetStdHandle(STD_INPUT_HANDLE);
if (hSaveStdin == INVALID_HANDLE_VALUE) {
  AfxMessageBox("hSaveStdin == INVALID_HANDLE_VALUE");
  CString s; 
  s.Format("Called GetStdHandle(STD_INPUT_HANDLE) - FAILURE# %d", GetLastError());
  AfxMessageBox(s);
}

The problem: GetStdHandle() with STD_INPUT_HANDLE or STD_OUTPUT_HANDLE returns INVALID_HANDLE_VALUE, but when I check the error code (with GetLastError()), no error code is denoted (zero is returned). Again, I didn't have this problem on my other box... Do you know what might be causing GetStdHandle() to fail (or actually, not fail, but return the aforementioned invalid value)?

In case you're wondering, I am using this to redirect the output of a console application (invoked with CreateProcess()) to file and to a control, but none of that happens until much later than these calls.

Careful that some other function is not clearing the last error output ie the messagebox.

Try calling GetLastError as soon as the error occurs, not after the messagebox.

"You should call the GetLastError function immediately when a function's return value indicates that such a call will return useful data. That is because some functions call SetLastError with a zero when they succeed, wiping out the error code set by the most recently failed function." MSDN

Something else to be aware of is GetLastError() is not fully implemented in 9x cored systems. A large number of functions in 9x, are still basically 16 bit, bodges. Many of these return zero, a few return rubbish.

Code:

hSaveStdout = GetStdHandle(STD_OUTPUT_HANDLE); 
if (hSaveStdout == INVALID_HANDLE_VALUE) {
  DWORD err = GetLastError();
  CString s; s.Format("Called GetStdHandle(STD_OUTPUT_HANDLE) - FAILURE# %d", err);
  AfxMessageBox(s);
}

Novacain:
Thanks for the tip. Here's what I changed it to, but still the last error is zero. Looks like adrianxw's comment may be the reason.

Dammit... Owell, I just decided to stop exitting the function upon the GetStdHandle() failure as it doesn't impede my function.

Thanks to both of you for the assistance.